
console.log(radius, pi)
//数学操作符 加、减、乘、除、幂、求余
//数学操作符 +  -   *  /   **   %
console.log(10 / 2)
//10除以3 余数1
let result = radius % 3
//计算圆的面积
let result = pi * radius ** 2
//括号优先运算
let result = 5 * (10 - 3) ** 2

let likes = 10
likes = likes + 1
//自增1
likes++
//自减1
likes--
//likes = likes + 10
likes += 10
//likes = likes - 5
likes -= 5
console.log(likes)

console.log( 5 / 'likes' ) // NaN , not a number
